China's smog crisis continues to plague Beijing residents and tourists as this past week's pollution levels reached almost 40 times the limit recommended by the World Health Organization, prompting the government to propose new regulations that could shut down nearby factories and better control car emissions.

Rapid industrialization combined with weak environmental regulations is to blame for Beijing's smoggy woes, which become more concentrated in the winter due to climate patterns and an increased demand for coal-powered heat.

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Photo: Feng Li/Getty Images

Hazy tourism

A tourist and her daughter wear masks on Jan. 23 while visiting Tiananmen Square in Beijing.

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Photo: Feng Li/Getty Images

Smoggy joyride

A woman wearing a protective mask bicycles down a smoggy street on Jan. 23 in Beijing.

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Photo: Feng Li/Getty Images

Shrouded in pollution

A man takes a stroll along a tree-lined path shrouded in heavy smog on Jan. 23 in Beijing.